Version v2.2.5 adds the igtools module to PYroMat, which allows uses to dynamically generate and modify gas mixtures and mixture arrays. All classes also now have new properties like speed of sound, Gibbs, and Helmholtz energies. Version v2.2.5 also corrects a number of long standing bugs. The most significant correction was to the R1234ze saturation property models, which had problems near the critical point.